ABSTRACT
Groundwater reservoirs play an important role in regional water volume balance. In order to ensure the efficiency of a groundwater reservoir and obtain its maximum value, it is necessary to figure out its characteristics, such as minimum water level, normal water level, and maximum water level. The characteristics not only determined the storage capacity but also influenced the water allocation and utilization. Therefore, this paper took a groundwater reservoir built in an alluvial fan as an example to assess its storage capacity and the influence on water dynamic control. The alluvial fan was located in the front of Lao River, where there were an alluvial-diluvial fan, groundwater storage space, and natural impervious boundary. Therefore, it was an ideal place for constructing a groundwater reservoir. Through theoretical analysis and numerical simulation, the storage capacity was determined, and the influence of groundwater reservoir characteristics on water dynamic control was analyzed. On this basis, the water-supply method in the research area was confirmed. This paper will present a new method for repairing the groundwater system and protecting the ecological environment.
Subject(s)
Groundwater , Water Pollutants, Chemical , Water/analysis , Groundwater/analysis , Water Supply , Rivers , Water Pollutants, Chemical/analysis , Environmental Monitoring/methodsABSTRACT
OBJECTIVE: This study sought to determine serum sclerostin (SOST) expression in patients with osteoporotic thoracolumbar vertebral compression fractures before and after percutaneous kyphoplasty (PKP). METHODS: Serum SOST levels were quantified with a sandwich enzyme-linked immunosorbent assay (ELISA) preoperatively and six months postoperatively. Anterior vertebral height, kyphotic angles, and Visual Analogue Scale (VAS) scores were also recorded. RESULTS: Serum SOST was highly expressed in patients and remained negatively correlated with bone mineral density (BMD). Vertebral heights, local kyphotic angles, and VAS scores were all significantly improved after PKP. However, serum SOST was positively correlated with BMD six months after surgery. CONCLUSION: PKP was an effective treatment strategy for osteoporotic thoracolumbar vertebral compression fractures, improving BMD and decreasing serum SOST levels. Level of Evidence II, Prospective comparative study.
OBJETIVO: Este estudo teve por objetivo determinar a expressão de esclerostina (SOST) em pacientes com fraturas vertebrais osteoporóticas por compressão na coluna toracolombar antes e depois da Cifoplastia Percutânea (PKP). MÉTODOS: Os níveis de SOST no soro foram quantificados por meio de um Ensaio de Imunoadsorção Ligado à Enzima (ELISA) sanduíche, realizado no pré-operatório e aos seis meses pós-operatório. Foram também registrados a altura do corpo vertebral anterior, os ângulos cifóticos, e os valores obtidos na escala analógica visual (VAS). RESULTADOS: O nível de SOST no soro foi altamente expresso nos pacientes, e permaneceu correlacionado negativamente com a densidade mineral óssea (DMO). As alturas vertebrais, os ângulos cifóticos locais, e as pontuações obtidas na escala VAS foram significativamente melhores após o PKP. No entanto, o SOST foi correlacionado positivamente com a DMO aos seis meses pós-operatório. CONCLUSÃO: O PKP foi uma estratégia eficaz para o tratamento de fraturas vertebrais osteoporóticas por compressão na coluna toracolombar, melhorando os níveis de DMO e diminuindo os níveis de SOST no soro. Nível de Evidência II, Estudo prospectivo comparativo.
ABSTRACT
ABSTRACT Objective: This study sought to determine serum sclerostin (SOST) expression in patients with osteoporotic thoracolumbar vertebral compression fractures before and after percutaneous kyphoplasty (PKP). Methods: Serum SOST levels were quantified with a sandwich enzyme-linked immunosorbent assay (ELISA) preoperatively and six months postoperatively. Anterior vertebral height, kyphotic angles, and Visual Analogue Scale (VAS) scores were also recorded. Results: Serum SOST was highly expressed in patients and remained negatively correlated with bone mineral density (BMD). Vertebral heights, local kyphotic angles, and VAS scores were all significantly improved after PKP. However, serum SOST was positively correlated with BMD six months after surgery. Conclusion: PKP was an effective treatment strategy for osteoporotic thoracolumbar vertebral compression fractures, improving BMD and decreasing serum SOST levels. Level of Evidence II, Prospective comparative study.
RESUMO Objetivo: Este estudo teve por objetivo determinar a expressão de esclerostina (SOST) em pacientes com fraturas vertebrais osteoporóticas por compressão na coluna toracolombar antes e depois da Cifoplastia Percutânea (PKP). Métodos: Os níveis de SOST no soro foram quantificados por meio de um Ensaio de Imunoadsorção Ligado à Enzima (ELISA) sanduíche, realizado no pré-operatório e aos seis meses pós-operatório. Foram também registrados a altura do corpo vertebral anterior, os ângulos cifóticos, e os valores obtidos na escala analógica visual (VAS). Resultados: O nível de SOST no soro foi altamente expresso nos pacientes, e permaneceu correlacionado negativamente com a densidade mineral óssea (DMO). As alturas vertebrais, os ângulos cifóticos locais, e as pontuações obtidas na escala VAS foram significativamente melhores após o PKP. No entanto, o SOST foi correlacionado positivamente com a DMO aos seis meses pós-operatório. Conclusão: O PKP foi uma estratégia eficaz para o tratamento de fraturas vertebrais osteoporóticas por compressão na coluna toracolombar, melhorando os níveis de DMO e diminuindo os níveis de SOST no soro. Nível de Evidência II, Estudo prospectivo comparativo.
ABSTRACT
We have attempted a multiscale and quantified characterization method of the contact in three-dimensional granular material made of spherical particles, particularly in cemented granular material. Particle contact is defined as a type of surface contact with voids in its surroundings, rather than a point contact. Macro contact is a particle contact set satisfying the restrictive condition of a two-dimensional manifold with a boundary. On the basis of graph theory, two dual geometrical systems are abstracted from the granular pack. The face and the face set, which satisfies the two-dimensional manifold with a boundary in the solid cell system, are extracted to characterize the particle contact and the macro contact, respectively. This characterization method is utilized to improve the post-processing in DEM (Discrete Element Method) from a micro perspective to describe the macro effect of the cemented granular material made of spherical particles. Since the crack has the same shape as its corresponding contact, this method is adopted to characterize the crack and realize its visualization. The integral failure route of the sample can be determined by a graph theory algorithm. The contact force is assigned to the weight value of the face characterizing the particle contact. Since the force vectors can be added, the macro contact force can be solved by adding the weight of its corresponding faces.
ABSTRACT
This paper attempted to provide a method to calculate progressive failure of the cohesivefrictional granular geomaterial and the spatial distribution of the stability of the cohesive granular slope. The methodology can be divided into two parts: the characterization method of macro-contact and the analysis of the slope stability. Based on the graph theory, the vertexes, the edges and the edge sequences are abstracted out to characterize the voids, the particle contact and the macro-contact, respectively, bridging the gap between the mesoscopic and macro scales of granular materials. This paper adopts this characterization method to extract a graph from a granular slope and characterize the macro sliding surface, then the weighted graph is analyzed to calculate the slope safety factor. Each edge has three weights representing the sliding moment, the anti-sliding moment and the braking index of contact-bond, respectively, . The safety factor of the slope is calculated by presupposing a certain number of sliding routes and reducing Weight repeatedly and counting the mesoscopic failure of the edge. It is a kind of slope analysis method from mesoscopic perspective so it can present more detail of the mesoscopic property of the granular slope. In the respect of macro scale, the spatial distribution of the stability of the granular slope is in agreement with the theoretical solution.
ABSTRACT
BACKGROUND: It is a challenge for orthopaedic surgeons to treat massive rotator cuff tears. The optimal management of massive rotator cuff tears remains controversial. Therefore, the goal of this study was to compare arthroscopic single- versus double-row rotator cuff repair with a larger sample size. MATERIAL AND METHODS: Of the subjects with massive rotator cuff tears, 146 were treated using single-row repair, and 102 were treated using double-row repair. Pre- and postoperative functional outcomes and radiographic images were collected. The clinical outcomes were evaluated for a minimum of 2 years. RESULTS: No significant differences were shown between the groups in terms of functional outcomes. Regarding the integrity of the tendon, a lower rate of post-treatment retear was observed in patients who underwent double-row repair compared with single-row repair. CONCLUSIONS: The results suggest that double-row repair is relatively superior in shoulder ROM and the strength of tendon compared with single-row repair. Future studies involving more patients in better-designed randomized controlled trials will be required.
Subject(s)
Arthroscopy/methods , Orthopedic Procedures/methods , Rotator Cuff Injuries , Rotator Cuff/surgery , Female , Humans , Male , Middle Aged , Outcome Assessment, Health Care , Recurrence , Treatment OutcomeABSTRACT
To predict the gaseous mass flow rate of microchannels, conventional analytical solutions based on the Navier-Stokes equation or volume diffusion hydrodynamics (bivelocity hydrodynamics) associated with first-order or second-order slip boundary condition are not very successful, especially in high-Knudsen-number flow. An analytical solution which agrees with experimental data to a Knudsen number of 50 is presented in this paper. To achieve this goal, a concept of effective volume diffusion is defined. Then, with a general slip boundary condition, the gaseous mass flow rate of microchannel is derived by solving the momentum equation of this effective volume diffusion hydrodynamics. Compared with six other analytical solutions and one group of numerical solutions of the linearized Boltzmann equation, this solution is validated by three groups of experimental data. The results not only illustrate an improvement of this solution compared with other analytical solutions but also show the importance of the effective volume diffusion hydrodynamics for compressible microfluids.
ABSTRACT
An online column enrichment-ultra high performance liquid chromatography (UHPLC) method was developed to determine trace carbaryl and carbofuran in water. The sample was injected into a UHPLC system directly after filtration with 0.22 microm membrane, and then enriched by online solid phase extraction (SPE) column. The analyte was back-flushed into the analytical column Acclaim RSLC C18 (100 mm x 2.1 mm, 2.2 microm) by valve switching method. The mobile phases were 10 mmol/L ammonium acetate buffer (pH 5.0, adjusted by acetic acid) and acetonitrile in a gradient elution mode with a flow rate of 0.8 mL/min, and detected by a diode array detector with the detection wavelength of 280 nm. The good linear ranges of carbaryl and carbofuran were 1.0 - 100 microg/L with the correlation coefficients (r2) larger than 0.9999, and the limits of detection (S/N = 3) were 0.5 microg/L and 0.25 microg/L, respectively. The average spiked recoveries were in the range of 76.0% - 120.0%. The method has been applied to determine trace carbaryl and carbofuran in water samples with satisfactory results.
